Recently, the number of the centers of providing school lunch, which are installed electrical kitchens is increasing gradually for hygiene control of foods and comfortable work environment. However, its ventilation and air conditioning system is often planned based on the techniques for gas kitchens, because the specific standards and methods of planning for electrical kitchens haven't established yet. Therefore, it can't be said that the features of electrical kitchen is considered on the planning of existing centers. For the planning of the ventilation and air conditioning system in the centers installed electrical kitchens, it is necessary to clarify the operating conditions of kitchen machines, because their operations have a significant influence on sensible and latent heat loads in the kitchen. In this study, we measured the electric power consumption of the kitchen machines of five centers with electrical kitchens for about 30 days. The centers were selected in consideration of the scale and the combination of kitchen machines. As the results, the electric consumption of washing machines is invariable daily, because they are operated in a similar way every day. On the other hand, in case of some cooking machines that are operated frequently for varied cooking purposes, their energy consumptions are quite differed from day to day. Therefore, the use with high output of latter machines does not carry on for a long time in daily operation.

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The experiments to study the vertical distribution of the pollutant concentration emitted from human bodies were conducted by means of scaled room with floor supply air-conditioning system. It was turned out that the semi-displacement ventilation flow is made in the room when the maximum throw of the supply jet is longer than the contaminant interface of displacement ventilation. Referring to the result of the experiments, simple zonal models for displacement flow and semi-displacement flow were constructed. In order to examine the validity of this prediction model, additional experiments under various supply conditions were conducted. The comparison between measured concentration and calculated concentraion lead to the proof of the validity of these prediction models for the practical design based on IAQ for occupants.

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The validity of thermal indices expressed in local environmental temperature, which signify the influences of plural local thermal factors, such as partial operative temperature, local equivalent temperature, etc. was investigated in order to evaluate the non-uniform thermal environment. It was ascertained that due to a variety of heat transfer rates at skin surfaces these indices can express local thermal states only in limited situations. Based on this idea, this series of study intend to obtain an evaluation and prediction method of human thermal comfort involved a sitting posture in non-uniform thermal environments. We planned to make express thermal comfort in terms of both local skin temperatures and local dry (sensible) heat losses. The results will be combined with a human thermal model that predicts local skin temperatures and local dry heat losses. Human subject experiments under radiant fields were carried out in a thermal booth (2,120mm×1,830mm×1,830mm) installed in a climatic chamber. The temperatures of a pair of opposite surfaces of the booth, i.e., floor and ceiling, front and rear panels, right and left parnels, were controlled independently through water circulation. A total of thirty-five thermal environmental conditions were created within ranges from 25.5℃ to 30.5℃ for air temperature, from 11.5℃ to 44.5℃ for temperature of radiation panels, from 40%RH to 50%RH for humidity, and less than 0.05m/s for inlet air velocity to the booth. A total of thirty-six subjects (18 men and 18 women) took part in the experiments. The subject was exposed to the condition for one hour while sitting in a low-insulative chair located at the center of the booth. Skin temperatures at twenty-five locations over the body surface were measured continuously, and both thermal and comfort sensations for overall and local area were recorded at intervals of 10 minutes. The following conclusions were obtained; 1) Skin temperature distribution changed depending on the magnitude of asymmetric radiant fields even if overall mean skin temperature was kept at almost constant value. 2) Increased magnitude of the radiant fields decreased the overall thermal comfort of the human subjects. 3) The local thermal discomfort was observed especially due to heat in the head area and due to coldness in the feet area respectively. 4) It is essential to use skin temperature distribution as well as mean skin temperature in order to express thermal comfort in non-uniform environments.

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Reducing energy consumption of the hot water supply system plays an important role in considering energy conservation in hospitals, residential buildings and hotels. Acquisition of water temperature data in water supply and distribution pipes in the region is essential to devising an energy conservation plan for the hot water supply system. Based on the statistical yearbook of the water works, we have analyzed water temperatures at 640 purification plants throughout Japan, and developed simplified prediction methods of water temperatures in distribution pipes. We further compared the predicted temperatures with actual temperatures of water in distribution pipes and tested the validity of the prediction methods.

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In the discussion about energy efficiency of heat source system, conventional studies have paid attention mainly to COP (co-efficient of performance) of refrigerators at rated condition (load factor 100%, cooling water temperature 32 degrees Celsius). However, COP at rated condition is not dominant factor in seasonal energy efficiency because operating time at rated condition is very short. In order to evaluate energy efficiency of heat source equipment appropriately, the operating condition all year around should be analyzed. This paper analyzes two types of district heating and cooling plants, absorption refrigerator and boiler system and electric heat pump system, by use of detailed measurement data with the aim of revealing the operating condition of heat source equipment. The results of analysis show that in well-designed and well-operated plants some refrigerators run only at the peak heat demand period such as daytime in summer, other refrigerators run almost at all season. Briefly, refrigerators have respective roles in producing heat according to refrigerator types and those capacities. It also comes to be obvious that cooling water temperature has strong influence on COP of refrigerators running at the peak heat demand period. In the next place, we estimate seasonal energy efficiencies of each refrigerator in the plants mentioned above by NPLV (non-standard part load value) method, which definition is based on IPLV (integrated part load value). The result shows that there is a difference between NPLV and real seasonal energy efficiency values from measurement data. This means that NPLV calculated in conventional way is not able to estimate seasonal energy efficiency with accuracy because IPLV definition can be applied to only single chiller system, not multiple chiller system and thermal storage system, both of which have already become popular. In addition, we suggest that IPLV/NPLV could be used for evaluating the operation condition of heat source systems.

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This paper demonstrates a laboratory experiments in order to investigate about thermal response for heat source (line or cylindrical) in the ground with ground water advection. The apparatus features to imitate ground water in a layer of sand filled into the apparatus. A prove buried in the sand layer can generate constant heat. Temperatures of the probe and each point in the sand layer were measured under a condition that the heat generation from the probe was constant. First, the experiments were carried out for several times by changing the ground water velocity. The time to achieve steady statement of the temperature change is shorter and the temperature is lower when the ground water flow is larger. Next, the each temperature variation calculated by the moving line source theory and numerical program applying finite difference method were validated by comparing with the measured one. The result showed that the calculated value reproduced the measured one. In addition, the authors proposed a method of estimation of the ground water velocity applying moving line source theory and estimated the velocity with experimental results as an example. As the result, it was confirmed that the errors between the velocities of the estimation with the method and the actual measurement are less than 100m/year or the relative errors are less than 20%.

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This report describes the results from the questionnaire and detailed survey conducted in 2004〜2006. The 10 items of questionnaire included in facilities management, maintenance management, saving energy, art gallery facilities. The number of museums investigated by questionnaire survey counted for public libraries about 241 in Japan. From the survey results, we discuss the tendency and characteristics about each item. This paper has emphasized the importance of having the facilities・maintenance management in public libraries.

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